Chowski



May 22, 1923.

G. A. YANOCHOWSKI TELE PHONE SYSTEM Original Filed April 25, 1917 I '2 27555 E5 WQL K Patented May 22, 1923.

UNITED STATES 1,455,954 PATENT OFFICE.

GEORGE A. YANOCHOWSKI, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCH-1 BOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLI.

' NOIS.

TELEPHONE SYS'IEIVI.

Application filed April 25, 1917, Serial No. 164,318. Renewed June 2, 1922. Serial No. 565,405.

To all whom it may concern lie it known that I, Gnoncn A. YANG- crrowsnr, a citizen of the United States of America, residing in Chicago, county oi": Cook, and State of Illinois, have invented certain new and useful Improvements in Telephone Systems, of which the following is a specification.

My invention relates to link circuits for telephone systems, being directed more particularly to link circuits having automatic ringing, secret service and automatic listening, peg count, and flash recall.

One 01": the objects of my invention is to provide a link circuit of the above character in which five relays only are used for controlling the supervisory and secret service system, and also the peg count and automatic ringing system. Other objects of my invention will behereinafter more particularly pointed out.

I have preferably embodiedmy invention in an operators cord circuit, and in carrying out. my invention when applied to the five relay arrangement, I employ an answerin supervisory relay which is energized when the answering terminal of the cord circuit is connected to a calling line whereby the operators telephone is connected in circuit with the calling substation. A second relay is provided in the nature of an opera! tors disconnect relay which operates when the calling terminal of the cord circuit is connected to a called line, the operation of the relay effecting the disconnection of the operators telephone. A third relay in the nature of a ringing control relay is pro. vided which is adapted to be energized upon a response from the called substation to disconnect the ringing current :trom the called line. A fourth relay is'provided to automatically switch the circuit of the answering supervisory lamp from a continuous source of current to an interrupted source of current, a fifth relay in the nature of a calling supervisory relay is provided by which a called substation controls calling supervisory signal,

For a better understanding oi my invention, reference is to be had to the accompanying drawing in which two telephone lines L and L are shown, the called line being of the party line type and having a plurality of substations connected thereto. Each of the line circuits includes a line relay LR and a cut-off relay OO together with multiple acks J, the calling circuit L having its parts indicated by large reference characters and the called line circuit L having its parts indicated by large reference characters with the suffix prime added.

The operators cord circuit C is adapted for interconnecting the telephone lines and has an answering plug P and a calling plug P connectedby so-called tip and sleeve conductors having the condensers K and K interposed. A relay AS is associated with the answering terminal of the cord circuit and serves as an answering supervisory relay, and also operates as an operators connect relay to connect the operators telephone set O with the link circuit when a call is answered. An answering supervisory sig nal SS is controlled by the answering supervisory relay AS and by the flash recall relay FR. The relay AS which is controlled over the calling line is connected to one terminal or the central o'flice telephone battery, the other terminal of the battery being con nected through an impedance coil D to the other strand of the link circuit so as to bridge the central oiiice battery across the talking conductors of the answering end of the link circuit for talking and supervisory purposes. An operators disconnect relay OD is connected to the calling terminal of the link circuit and operates to disconnect the operators telephone from the link circuit when the calling plug P is connected to'the called line.

Owing to the fact that the operators telephone is connected through normally closed contacts of relay OD, it will be apparent that as long as the plug P is in connection with a link circuit the operators telephone O is disassociated with the link circuit, giving so-called secret service in which the op operator cannot listen induring a connec-v tion between two telephone lines. The op eration of relay ODis also effective to connect ringing current from one of the rin ing genra-ators oi": the ringing apparatus ll to the terminals of thecalled line, and when. a response is secured from the substation on this line the ringing control relay ROB. is operated to disconnect the ringing current therefrom. The upper winding 4 of the ringing control relay ROE is adaptedto be included in the path for the ringing current by anon-inductive 'shuntwinding 5, preferably "Wound upon "the core of said relay RCR, and provides a more ready path for the -ringing current when the called line is being signalled. When "applying ringing current to the called line, it is preferable to disconnect the answering end of the link circuit from the calling end so that the ringing current will not flow backover the callin line, and to provide this feature I provide contacts controlled bjythe relay RCR whichare included in the talking strands of the link circuit. To prevent the application of the ringing current after the called subscriber has responded and replaces his receiver upon its switch hook, I provide a locking winding 6 for relay RCR so that when it once energizes it will remain energized until the relay 'OD is deenergized by the disconnection of the plug P from the jack of the called line. To make the relay BUR sensitive and still have suflicient attracting power to perforin its work, I arrange the contact springs 7 to make before the other springs are operated, thereby closing a local energizing circuit for winding 6j/o'f relay RCR at whicl'i time the continued attraction of. the armature of relay IiCR opcrates the other springs controlled by said relay. An advantage of such an arrange ment is that 'this relay which. is initially energized over-the called line circuit starts the attraction-of its armature under the 'tensi on of but asingle contact spring until this local contact circuit is closed. after which I the other springs are operated, and in this way a c'oinparatively large number of contacts may be operated by a relay which is initially "controlled over the subscribers line circuit, which may vary considerably in resistance. I

A calling supervisory signal SS is associated with the calling plug P and is caused to glow when the plug P is inserted into the jack J to the called line, and eiiaced when the called subscriber responds by removing his receiver from its switchhook.

To economize upon space, I combine the impedance coil D and the calling super visory relay CS in one structure whereby I secure an evenly balanced talking circuit, that is, at the answering end of the cord circuit a full winding is. connected to the tip side and a half Winding to the sleeve 1 side While at the calling end a half winding isconnected to the tip side and a full windingto the sleeve side of the circuit. The

' impedance winding D is non-inductive and does not affect the magnetic circuit of the calling supervisory relay OS; If it is desired, the magnetic circuit of winding CS may be entireliyiisolated from Winding D'although included in the same structure. When applying my invention to party line ringing, I provide a well known form of party line indicating key having contact sets 11, 12, 13 and 14, corresponding in number to the number of frequencies, these contacts being closed when the plungers are in their intermediate locking and indicatingaposition.

In the preferred method of operation, the proper ringing plunger is depressed before the calling plug P is inserted into a jack, this arangeinent being preferred because in using a locking party line ringing key one of the ringing contacts is always closed so that I prefer to select the desired frequency before the plug is inserted into the called jack. Preferably, I provide the Well known ringing system which includes four ringing generators, 15, 16, 17 and. 18, which generate ringing current of the required frequencies to operate the call bells at the party line substation telephones. Each of the ringing generators is connected through a periodically closed contact, there being, therefore, four'such contacts 19, 20,21 and 22, which may be 0 aerated by any source of power to periodical y close the ringing contacts 23, 2%,25 and 26.

In order-to insure the operation of relay RCR when the receiver is removed. the called substation, I provide a source of direct current 2? in connection with the ringing device H, which source is preferably a separate source from the talking battery, and may consist of dry cells, and has one of its poles grounded so that when the vibrating contacts 19, 20, 21 and 22 are closed during the silent interval this battery is coni nected in series with thecord circuit battery,

giving a higher potential so that a more positive operation of relay RCR is secured,

From inspection, it will be apparent that the peg count device K, by which the number of "answered calls by each operator is recorded, comprises a relay 28 of high -re sistance and impcdence which is common to each operatorsposition and which is adapted to be energized each time a calling plug P of its corresponding position is inserted in the jack of a subscribers line to answer a call. The operation of the relay 28 closes a circuit through a meter n'iagnet 29 which operates to record the callupona meter.

The flash recall relay Flt-,which controls the flashing and the supervisory lampSS when a recall is desired, is provided with a locking circuit that after once being closed at ains the relay FR energized until the calling plug I is disconnected from the jack of the calling subscribe1"s line. The relay FR controls the association of the in terr-upter I with thesupervisory lamp SS.

Now having described in general the embodirnent of ny invention as illustratechits operation will now be described. I

Assuming a subscriber, at substation X has removed his receiver to initiate area-ll,

the line relay LR is energized over the calling line in a well known manner to operate the associated line signal S, whereupon the operator inserts an answering plug P into a jack J of the calling line, establishing an energizing circuit for cut-off relay CO and supervisory relay AS. The operation of the cut-off relay CO is effected by a circuit traced from battery through the winding of impedance coil D, answering sleeve conductor, sleeve contacts of the plug and jack, and the winding of relay CO to ground. This circuit does not affect the armature of relay CS. The relay CO energizes over this circuit and operates to disconnect the line relay LR and extends the conductors of the line X to the answering end of the cord circuit. The receiver at the calling substation being ofli its hook, there is a flow oi. current through impedance coil D and out over the called line returning over the tip side of the cord circuit and through the winding of the answering supervisory .relay AS to ground. Relay AS energizes over the above-traced circuit and interrupts its normal contacts 30 and 81 so that the lamp SS cannot be operated until the calling subscriber has replaced his receiver. A further result due to the energization of relay AS is the connection of operators telephone O to the strands oi the link circuit through its alternate contacts 32 and 33.

The closing of the alternate contact 32 of relay AS also closes a circuit for the meter-controlled relay extending from battery through thenon-inductive winding 1) of relay OS, through normal contact 34 of relay OD, through alternate contact .33 of relay AS and the winding of the relay 28 to ground. The relay 28, upon energizing, closes a circuit for the meter control magnet 29 traced from battery through the winding of said magnet 29 and through alternate contact 60 of relay 28 to ground. The magnet 29 upon energizing, operates to register a call upon the counting mechanism.

The operator now inquires the number of the desired subscriber and tests the jack J of the called line by applying the tip conductor of the plug P to the bush of a jack of the called line in the usual manner and finding the line idle inserts said plug P into the said jack J after having pressed the proper ringing button of the ringing apparatus H. The connection of plug P to thejack J closes an energizing circuit for the disconnect relay OD and the cut-ofi' relay CO causing the energization of these relays by currentover a circuit traced from battery through the winding of OD, sleeve contacts o1 plug P and jack J and the winding of cut-oft" relay CO to ground. The operation of relay CO removes the substation control of line relay LE in the usual manner, and the operation of relay OD effects the disconnection. of the operators telephone O by reason of the interruption of normal contacts 34 and 35.

A further result due to the energization of relay OD is the closing of a circuit for calling supervisory lamp SS over a circuit traced from ground through alternate contact 36 of relay OD and through normal contact 37 of relay OS and said lamp S55" to battery. A still further result due to the energization of relay OD is the application of ringing current to the called line by reason of the closing of alternate contact 38, the path for-ringing current being traced from generator 15, (which we will assume is a selected generator by reason of its op erated contact 11.) through alternate con tact 23, alternate contact 1.1, ringing conductor 40, windings 4 and 5 in multiple, alternate contact 38 of relay OD, normal contact 41 of relay ROB, tip side of the link circuit over the called line, including the substation call bell, returning over the sleeve conductor to point 42 Where the current divides, part of it flowing through relay OD and battery to ground, and part of it flowing through normally closed contact 43 and winding 44 to battery and to ground.

Each periodical closure of alternate contact 19 of the ringing device H, of course, causes an operation of the call bell, and when the called subscriber responds by removing his receiver in response to the call and upon the following closure of alternate contact 45 of the ringing device, due to the removal of the condenser at the substation, a path for direct current through the winding 4 of the ringing control relay ROR is established to cause the initial energization thereof.

As already stated, when the contact 45 is closed, ringing battery 27 is connected in serieswith the cord circuit battery, providing a higher potential for operation of the ringing control relay than iii only the cord circuit talking battery is used. This circuit may be traced from battery 27 through alternate contact 45, over the previously described path for ringing current, and back through the relay OD and winding 44 in multiple to the cord circuit battery. The How of current through the initial energizing winding 4 of relay ROR causes the attraction of its armature, whereby its contacts 7 are first closed to bring the local energizing winding 6 in circuit to cause the continued attraction of the armature which interrupts normal contacts 41 and 48, thereby disconnecting the ringing current and closing alternate contacts 41 and 43 to establish the continuity of the talking circuit. The closing of alternate contact 41 connects the calling supervisory relay OS in circuit with the line so that battery flowing through the relay OD and out over the called line returns over the tip side of the link circuit, through alternate contact 4C1 of relay RC3, and winding of said relay CS to ground. The relay CS, upon energizing, operates to interrupt its normal contact 37, thereby cti'acing the calling supervisory lamp It will also be noted that relay litllt interrupts its own initial energizing circuit through its normal contacts 41 and 43 but not until its l cal circuit is closed.

The substations X and are now connected inconversational circuit, the talking battery being ted orer the heavily marked conductors to the calling and c ed line. During the connection of the linlr circuit with the calling and called ""ies, it is impossible tor the o ierator to listen in to the conversation, due to the fact that her telephone has been disconnected from the link circuit by reason of the interrupter contacts 34L and '55 of relay GD cannot again be closed untilth'e plug F is withdrawn from the connected jacl: J After the subscribers have vfinished their conversation, they will replace their respective receivers upon their switch hooks, this act at the calling sub-v statio X causing the restoration of an swering siiipervisory relay [iii and thereby closing the energizing circuit for the answering supervisory signal and the flash recall relay Flt, while the restoration of the receiver the called substation Y causes the restoration of the calin'lg supervisory relay CS, thereby closing a circuit for the calling supervisory lamp SS The circuit for answering supervisory lamp SS extends from battery through said lamp, armature 50 and contact 30 of relay and through alternate contact 36 oi": relay GD to ground. The circuit for flash recall relay Flt extends from battery through the winding of said relay Flt, contact 31, armature 50, and con tact 30 of relay AS, and through alternate contact 36 of relay DD to ground.

Relay Flt upon energizing, closes a looking circuit for itself through its alternate cont-act 51, independent oi the arn'iature 50 of relay AS. The locking circuit for relay extends from battery through winding of relay FR, its alternate contact 51, and through alternate contact 36 of relay UI) to around. The circuit for the calling superv. iry lamp in) extends trom battery through the said lamp Sil normal contact 3'? oi relay CS and through alternate con tact 86 oil relay 0] to ground.

The operator in response to the glow of supervisory lamps SS and Stil removes plugs P and, P from their respective jacks,

, the withdrawal of plug P causing the dc energization of relay OD and by reason of the interruption of alternate contact 36 ct tects the restoration of relay RUE, the withdrawalof plug P causing the restoration 0t iliitQlQ for use in establishing other contu d the subscriber at substation X'desire to cake a recall before the plugs P and i ct cord circuit C have been with drawn from the r respective jacks, he removes his receiver from its switch hook, thereby again closing an energizing circuit tor relay i i-55 over the circuitherein-before traced. Relay AS this ime upon energizing switches the circuit of the calling supervisory lamp ti from ground at alternate cci'itact 235i oi": relay til) to interrupted ground sa'zpplied by the interrupter I over a circuit traced tri'un battery through said 7 isory lamp 55, armature 50 and contact of relay 135i, alternate contact 57 of re iy Fit, and through theinterrupter I to rand. Theinterrupter I causes tliesupervisory l: 1p SS to be flashed intermittently to notify the operator that a recall is desired by the c ling; subscriber and that she should e this iall her immediate attention. The operator now removes the calling plug P troin the jack 5 of the called subscribers line, thereby permitting the relay OD to de- GHGI'QMG and agai connect the operators telephone set O to the strands of the link inquire the wants of the calling it the same time that the op tor s set in again connected to the strands or the link circuit, the locking circuitsyfor relays FE and are opened at contact 36 ot' relay OD. The operator after receiving the desired information from the calling subscriber completes the connection with the desired called line in the same manner as her in-before described.

l1 ad the calling subscriber initiated a recall betorethe calledsubscriber responded, the relay FR alone would have been deenergized when the operator removed the alled plug P from the jack ot the called subscriber to reconnect her telephone set 0 to the strands of the cord circuit. The replacing of the receivers at the callingand called subscribers substations operates the siuaervisory signals in the same manner as herein-hetero described.

From tl c foregoing, it will. be apparent that it am enabled to accomplish the following reatures: automatic ringing, secret service and automatic listening, flash recall and pop; count with the provision of only five relays to a cord circuit,

While if have illustrated a preferred embodiment of my invention. it is apparent that it may be applied in various ways and also that many modifications and changes will. readily suggest themselves tothose Therefore, I do not de' skilled in the art. sure to be limited to the exact structure as shown, buuaim to cover all that which comes within the spirit and scope of the appended claims.

What claim as new, and desire to secure by United'states Letters Patent 5 z 1. A telephone systen: incl'u, subscribers telephone lines, an operator s link circuit for interconnecting said lines, a con trol relay controlled over a connected subscribers telephone line, an operator-"s telephone, circuits controlled directly by said control relay for connecting said operators telephone to said link circuit, an a iary relay, a circuit for said auxiliary relay adapted to be closed by the de-energization of said control relay, a locking circuit for said auxiliary relay independent oi its energizing circuit, a supervisory lamp, and a circuit for said supervisory lamp including contacts of said auxiliary and control rclays and adapted to be closed when said relays are both energized.

2. In a telephone system the combination with a subscribers telephone line and a link circuit connected thereto, a relay controlled over said subscribers line, an operators telephone, circuits controlled directly by said relay for connecting and disconnecting said operators telephone and said link circuit, a supervisory signal and an auxiliary relay, circuits for said supervisory signal and said auxiliary relay adapted to be closed by the de-energization of said first relay, and a second circuit for said supervisory signal including contacts of said first relay and said auxiliary relay and adapted to be closed when both of said relaysare energized.

3. A telephone system comprising tele phone lines, a link circuit provided with only five relays for interconnecting said lines, ringing apparatus and a pair of supervisory signals for said link circuit, one of said relays being adapted to control one of said supervisory signals, the second of said relays adapted to connect the ringing apparatus to a called subscribers line,the third ,of said relays adapted to disconnect the ringing current from the called subscribcrs line, the fourth of said relays adapted to directly control the other of said supervisory signals, and the fifth of said relays adapted to include an interrupter in circuit with said first supervisory signal to indicate that a recall is desired.

4. A telephone system including telephone lines, a link circuit provided with only five relays for interconnecting said lines, ring ing apparatus and a pair of supervisory signals for said link circuit, one of said relays being adapted to control one of said supervisory signals, the second of said relays adapted to connect said ringing apparatus to a connected telephone line, the third of said relays adapted to disconnect said ringing apparatus from said subscribers line, the fourth of said. relays adapted to directly close a continuously operating circuit for said other supervisory signal, and the fifth of said relays being controllable by the fourth of said relays for closing an intermittently operating circuit for said. last supervisory signal.

In a telephone system the combination with a subscribers telephone line, oit aplug ended link circuit connected therewith, a single wound relay for said link circuit controllable over said. subscribers telephone line, an operators telephone, circuits controlled directly by said relay for connecting and disconnecting said opcrators telephone and said link circuit, a supervisory signal, a continuously operating circuit for said signal adapted to be closed by the de-energization of said relay, and an intermittently operated circuit for said supervisory signal including contacts of said relay and adapted to be closed by the re-energization of said relay.

6. A telephone system including a subscribers telephone line, a link circuit, a relay for said link circuit adapted to be connected to said telephone line, a supervisory signal, a movable and three relatively stationary contacts for said relay, a continuously operating circuit for said signal including said movable and one of said stationary contacts, an intermittently operated circuit for said signal including said movable and another of said stationary contacts, and an auxiliary relay connected to the third of said stationary contacts, energized upon the de-energization of said first relay for controlling a contact in said intermittently operated circuit.

7 In a telephone system including an operators link circuit, a relay for said link circuit, a movable and three relatively sta tionary contacts iior said relay, an auxiliary relay, a supervisory signal, a continuously operating circuit for said supervisory signal including said movable and one of? said stationary contacts, a circuit for said auxiliary relay including another of said stationary contacts and adapted to be closed upon the de-energization of said first relay and an intermittently operated circuit for said supervisory signal including said movable and the other of said stationary contacts and a contact controlled by said auxiliary relay.

8. A telephone system including a calling and a called subscribers line, a link circuit for connecting said lines in conversational circuit, an operators telephone, automatic means for connecting and disconnecting said operators telephone and said link circuit, a pair of supervisory signals, means for con trolling continuous circuits for said signals and for closing an intermittently operating circuit for one of said signals, and means for automatically ringing said called subscriber, all of said above means being; controlled by only five relays.

9; A telephone system including a calling and a called subscribers line, a link circuit provided With only five relays for connecting said lines in comrersational circuit, said link circuit being provided with automatic listening, flashing recall, automatic ringing and automatic disassociation of the ringing; current from the called line, all of said features being controlled by said five relays.

10. A telephone system including a calling and a called subscribers line; a link circuit provided With only five relays for connecting said lines in conversational circuit; said link circuit being provided with means. for automaticallyconnecting an operators telephone With said link circuit, for intermittently operating a supervisory signal, for automatically connecting to and ringing the called subscribers call bell, and for automatically disassociating said ringing means from said called substation; said means all being controlled by said five relays. I

Signed by me at Chicago, in the county 01'' Cook and State of Illinois, this 23dday of April, 1917.

GEORGE A. YANOCHOVVSKI. 

